A fixing apparatus for fixing a slide rail to a first column and a second column includes a first fixing member, a release member, and a second fixing member. The slide rail includes a flange formed perpendicularly at a first end of the slide rail. The first fixing member attached to and slid along the first end of the slide rail includes a tab. The tab and the flange sandwich the first column. The release member attached to and slid along to the slide rail includes a latching hook formed at a first end to engage with the first fixing member, a mounting tab extending from the release member adjacent to a second end, and an opening adjacent to the mounting tab. The second fixing member attached to the second end of the release member includes a fixing tab. The tab and the mounting tab sandwich the second column.